ecj1 software package provides java byte code compiler used by gcj, you can install in your Debian 8 (Jessie) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install ecj1
ecj1 is installed in your system.
Make ensure the ecj1 package were installed using the commands given below,
$ sudo dpkg-query -l | grep ecj1 *
You will get with ecj1 package name, version, architecture and description in a table
| Distro | Debian 8 jessie |
| Section | Java |
| Package | ecj1 |
| Version | 3.10.1-1 |
| Description | java byte code compiler used by gcj |
| Sub Section | Java |